Cleanup net integration test case for network modules (#34684)

*  Remove platform agnostic net_* test cases.
*  Add minimal platform agnostic test cases to individual
   platform-specific test cases

test/integration/targets/eos_user/tests/cli/net_user.yaml

@@ -0,0 +1,41 @@
+---
+- debug: msg="START eos cli/net_user.yaml on connection={{ ansible_connection }}"
+
+# Add minimal testcase to check args are passed correctly to
+# implementation module and module run is successful.
+
+- name: Set Up
+  eos_config:
+    lines:
+      - no username ansibletest1
+    provider: "{{ cli }}"
+  become: yes
+
+- name: Create user with role using platform agnostic module
+  net_user:
+    name: ansibletest1
+    privilege: 15
+    role: network-operator
+    state: present
+    configured_password: test1
+    authorize: yes
+    provider: "{{ cli }}"
+  become: yes
+  register: result
+
+- assert:
+    that:
+      - 'result.changed == true'
+      - '"username" in result.commands[0]'
+      - '"secret" in result.commands[0]'
+      - '"role network-operator" in result.commands[1]'
+      - '"privilege 15" in result.commands[2]'
+
+- name: Teardown
+  eos_config:
+    lines:
+      - no username ansibletest1
+    provider: "{{ cli }}"
+  become: yes
+
+- debug: msg="END eos cli/net_user.yaml on connection={{ ansible_connection }}"